Jack Grounding

[R2D2]

Hi all,

We have just traveled through the south to Orlando and with all the lightning something came to mind. I have, but don't usually use plastic pads under the jacks. We usually set up on concrete/asphalt pads so I didn't think they were necessary. However, is this a mistake? Do they become a ground for the motorhome and if so, is that a problem?

Look forward to your thoughts.

Thanks,

Fred

PS- I apologize if this is not the correct forum for this topic. Please move appropriately.

[thompwil]

Here's an interesting RV article that addresses your question near the end, short read...

Lightning Safety | No~Shock~Zone


More interesting stuff...
http://noshockzone.org/category/rv-safety/

[R2D2]

Very interesting reading.

Thank you!

Fred

[NeilV]

The pads would offer little to no resistance against lightning. Your biggest danger will be from surges caused by lightning coming in through campground electrical and cable tv wiring as far as lightning is concerned.

A bigger concern would be low voltage damage to your transfer switch, air conditioning and appliances 110 volt circuits. Surge Protection and Low Voltage Correction can save you a lot of money on repairs over the long haul.

[Jim_HiTek]

I would use my wooden pads under my jacks down there.

It's long been advised that during a lightening storm you should stow everything. Including the shore power cord. So only the tires are touching the ground. You just sit and wait it out without power. Maybe listen to your weather radio to pass the time.

Some of the lightening storms I've seen over the 15 years I've been full timing have been nearby and really wild, but I've only followed that advice a couple times when a storm came right at me. And both times that was in Florida.

[Meridian42e]

Originally Posted by Jim_HiTek

I would use my wooden pads under my jacks down there.

It's long been advised that during a lightening storm you should stow everything. Including the shore power cord. So only the tires are touching the ground. You just sit and wait it out without power. Maybe listen to your weather radio to pass the time.

Some of the lightening storms I've seen over the 15 years I've been full timing have been nearby and really wild, but I've only followed that advice a couple times when a storm came right at me. And both times that was in Florida.

That advise is nonsense. Tires themselves are not "insulating" you from ground, as tires have a high carbon content which is an excellent conductor for high voltage (used in spark plug wires). Stowing the shore power cord does remove the exposure to park surge, but also removes your earth ground - toss up. Jacks down or up, doesn't matter. Lowering antennas for the lowest profile is about all you can do.

[Jim_HiTek]

Originally Posted by Meridian42e

That advise is nonsense. Tires themselves are not "insulating" you from ground, as tires have a high carbon content which is an excellent conductor for high voltage (used in spark plug wires). Stowing the shore power cord does remove the exposure to park surge, but also removes your earth ground - toss up. Jacks down or up, doesn't matter. Lowering antennas for the lowest profile is about all you can do.

Where does my post say anything about 'insulating' you from ground?

The reason I put wood under the jacks and stow the shore lines in the event of a nearby lightening storm is to reduce the number of paths lightening might take as it finds it's path to ground in/around my RV (which is somewhat like a large metal cage). I'd much rather have it travel through/over the tires only. The only time I go to this extreme is if it's a doozy of a storm and it's path will take it right over the RV park I'm in. And it depends on how long it's likely to last. A 15 minute storm won't make me go to that extreme.

I'm trying to keep it from traveling through the metal front window frame, arc into the several electrical devices in the entertainment cabinets, through their grounds, through the A/C wiring, through the shore power cord to earth ground. That also goes for other electrical devices on board.

Having seen the electrical devices that are UNPLUGGED from AC have a far better chance of being undamaged then those items that are plugged in during a lightening strike, I prefer to do it this way. Home or RV. And to me an RV is just a giant electrical device plugged into power.

"Rubber tires aren't why you're safe in a car during a lightning storm. In strong electric fields, rubber tires actually become more conductive than insulating. You're safe in a car because the lightning will travel around the surface of the vehicle and then go to ground."

"According to the Department of Homeland Security, you should unplug all of your appliances. This is because lightning striking near a local electric pole can cause a surge of electricity..."

Unplugging the entire RV seems to me to be nearly the same thing as unplugging all the appliances.

[R2D2]

Thanks for the info and replies! Been on the road for awhile.

About two weeks ago a neighboring space about 60 ft. away had a lightning strike issue. It struck a palm tree next to their trailer, glanced to the ground about 5 ft. from the trailer and truck. A 2x2 chunk of concrete exploded and the lightning scattered. I don't know how it entered the truck or trailer, but it wiped out all of the circuits in the trailer; fridge, entertainment components, etc. Their insurance totaled the truck due to extensive electrical damage. They have had all components replaced in the trailer and are able to occupy it again. They are still waiting for their truck to be replaced so they can get back to Maine. FWIW, the trailer is on wood and concrete blocks and the truck was not in contact with the trailer.

When the lightning scattered it also traveled a couple hundred yards and took out the campground wifi repeater tower.

Thanks again,

Fred

[Wakullabob]

Lightening does what ever it wants . Our motorhome was next to a power pole that was hit by lightening , killed all appliances and $8,000 computer in Mercedes .
In an offshore sailboat race we were struck with little damage in our 49 foot ketch. Offshore I have seen shrimp boats struck with no damage . Lightening is searching for the path to earth which is closest and has least resistance .